If He had destroyed their idols, and had not smitten their first-born... Dayenu, it would have sufficed!

Ilu asah beloheihem,v'lo harag et b'choreihem,dayeinu!


אִלּוּ עָשָׂה בֵּאלֹהֵיהֶם
וְלֹא הָרַג אֶת בְּכוֹרֵיהֶם


 

haggadah Section: Karpas
Source: http://en.wikipedia.org/wiki/Dayenu